The instant invention relates generally to the transport of crop harvesting implements, and more particularly to a method and apparatus for preventing damage to either the transporter or implement due to improper conversion into transport position through utilization of an automatic cutoff valve in the hydraulic fluid system.
A mower-conditioner is used for the harvesting and processing of hay and other crops. The harvester is typically towed by a tractor and powered by either a hydraulic pump or the PTO of the tractor. A pivoting tongue connects the harvester to the tractor during operation and transportation.
The cutting means of the harvester consist of either a sickle bar or rotary disc mower that may be accompanied by a conditioner to remove moisture from the harvested hay or crop material. If conditioned crops are desired, the crops are passed through a pair of rubber covered conditioning rolls or through a set of metal flails. The means of cutting and conditioning are well known and well described in the prior art. The processed crop is left to dry on the field and is usually further processed by a baling mechanism.
Generally, harvesting equipment, particularly hay harvesting equipment, has been designed and manufactured with a transverse width that would permit transport thereof over the highway and through farm gates. Although the hay harvesting machines commonly referred to as pivot tongue windrowers, such as those shown in U.S. Pat. No. 4,081,946, granted in 1978 to Philip J. Ehrhart, were generally wider in a transverse direction than previous pull-type hay harvesting machines, the centrally mounted pivoted drawbar permitted towing of the harvester directly behind the tractor in a centrally located position and, therefore, transport of the harvester in a normal operational orientation was possible.
The width of the mowers has been increased over the years in order to improve productivity and the efficiency of harvesting hay or crop material. This increase in mower width has necessitated an alteration in the means of mower transport, as increasing transverse widths have prevented harvesters from being towed in an operable position behind the tractor over highways and through restrictive openings.
The development of the pivot tongue harvester with a laterally extendible drawbar, as disclosed in U.S. Pat. No. 4,558,560, permits the harvester to be mounted on a transporter and transported in a lateral orientation by utilizing the drawbar of the harvester as the hitch connection to the tractor. In order for transport, the implement is backed onto a transporter or trailer and the tongue is pivoted 90 degrees from the standard transport position. A trans
When an implement is loaded on a transporter and the tongue of the implement is rotated to an endwise position and used to tow the implement and transporter, the driveline has to be disconnected. This step can easily be forgotten and damage can occur to the driveline and shielding on the implement.
In order to prevent damage to the driveline and shielding on the implement or damage to the transporter, there exists a need for an apparatus that prevents the tongue of the implement from rotation into the endwise transport position without first disconnecting the driveline between the tractor and the implement.
It is an object of this invention to provide an adaptation to the hydraulic system of an implement that prevents the tongue from pivoting beyond the operational limits of implement when it is being loaded onto a transporter.
It is another object of this invention to provide a hydraulic selector valve between the hydraulic source and the cylinder that controls the swing of the pivot tongue in order to block the flow of hydraulic fluid to the swing cylinder when the limits of the desired swing arc are reached.
It is another object of this invention to provide a harvester with a pivot tongue that cannot swing into a transport position on a transporter without the prior detachment of the driveline and steering link.
It is another object of this invention to provide a method and apparatus for preventing damage to the driveline, steering link, and gearbox that does not rely upon complex or expensive to produce components.
It is another broad object of this invention to provide an improved implement hydraulic system that cooperates better with a transporter than those heretofore known.
It is a still further object of this invention to provide an agricultural harvesting implement that works with a lateral transporter for carrying the implement in a transverse orientation that is durable in construction, inexpensive of manufacture, low in maintenance, facile in assemblage, and simple and effective in use.
These and other objects, features, and advantages are accomplished according to the instant invention by providing a pivot tongue crop harvester having an hydraulic system to selectively swing the pivot tongue about a pivot point on the harvesting mechanism, including a selector valve to cut off flow of hydraulic fluid to the tongue swing cylinder during loading of the harvester onto a transporter if the driveline of the harvester has not been disconnected.